Air driven tow target reel



Jan. 22, 1957 w. w. WILSON AIR DRIVEN Tow TARGET REEL 4 Sheets-Sheet 1 Filed Nov. 2l, 1955 mw .s .IW` 50m W4; mw www Jan. 22, 19.57 W, w, wlLsoN 2,778,584

AIR DRIVEN TOW TARGET REEL Filed Nov. 2l. 1955 4 Sheets-Sheet 2 Jan. 22, 1957 2,778,584

W. W. WILSON AIR DRIVEN TOW TARGET REEL Filed Nov. 21, 1955 4 Sheets--Sheei'l 3 IN VEN TOR. WEdW W W S 0N Jan. 22, 1957 Filed Nov. 2l, 1955 W. W. WILSON AIR DRIVEN TOW TARGET REEL.

4 Sheets-Sheet 4 A? fra Mf- Ys AIR-DRIVEN TOW TARGET. REEL,

Woodrow Wilson, Norman, Okla., assignor'J to the United Statesof Americaasflrepresented'b'y theSecre tary of'the AinFor-ce Application November 21,1955, SerialfNo. 548,284 6 claims. (or.v 244-3)l (Granted under 'rifle ssU.s..Code ;(19sz)sec. 266) of the airstreamy on the winddrivenactuating means to control the windingaction^or interrupt the eitective actuating forceof'the air'streamon the. device during.,ilight to permit controlled' unwinding. action of a tow cable drum in the device;

A further object is the provision of' a unitary device which can-be easily and' convenientlyattached to and'detached from theV exterior' ofi an aircraft and includesa wind-'driven tow target winding reel andwhich is suspendable from a conventional typeof .supporting hangers similar to' a bomb or rocket launcher racks below the fuselage or wing'ofan aircraft'.

A further-object includesmean's formounting the windingreel device withV its winding drumk axis ,in the ilight axis direction.r

A still-further objectincludes"controllable brake means for' controlling the' rotation' of ithe drum.

A further objectA includes= a winddriven level'winding cable' reelidevice for gpidingorlevelirig the coils of' the tow cablein l juxtaposed sideby-'sidemrelation as the tow drawing the tow target into*- a towtarget receiving and supporting-receptacle; l f v n A- further objecty of the--inventionii's the provision of an elongated casing means adaptedf to ybie suspended below the fuselage of an aircraft; havingn the tow targetk cable reel'means journalledthereirr with-its axis substantially Parallel to tliee'axis of the-aircraft andlocatedinterrnediate and below the level of tlteleading and trailcompanying drawingsv in which like reference characters 4refer to like parts in the several gures.

Drawings Figure lis a side. elevation of my improved wind-driven tow `target device.

Figure 2U is a rear endview of the device shown in Figure l.

Figure 3 isa longitudinal sectional view taken about `ony lineV 3 3 of Figure 2, looking in the direction of the arrows.

Figure 4 is a front elevation illustrating the buttery lor shutter valve closed.

' Figure 5 is a somewhat diagrammatic View in side elevation of a jet aircraft showing the wind-driven tow target'"cable reel device suspended therefrom', including the ywing tipy tow target supporting meansy with a tow target supported therein.

Figure 6-is a somewhat schematic perspective view of the-streamlinedtwing'tip tow'target' supportwith the nose ofthe'tow target retained therein by the tow line, also showing` the tow line extending laterally into the winddriven tow" target reel or cable winding device, dotted lin'es showing the tow target and attached line slightly withdrawn. v

Referring to Figures 5 and 6, the reference numeral 1 ydenotesv a jet aircraft 'having a fuselage 2,' wings 3, and

ak streamlined" wing tiprtank and tow target supporting means-4 in therear end of which is formeda ared re- Iceivir'ig opening/5 in which a streamlined tow target 6 is`received and` supported. The tow target wind-driven cable reel device is indicated at 7' and the tow cable Referring-now to Figures 2, 3 and 4 more particularly, the reel` device comprises a cylindrical supporting casing 9having`somewhat streamlined rear and front sections or closure shells 10 and 11 and spaced transverse supporting plates or discs 12 and 13. These plates12 andf1'31have-hub'portions-12"andi13 in which'are journalledf'ionantifriction bearings 12a and 13a, the main or reel shaft 1f4on whichis concentrically ixed` a tow target. cable winding reel or spool 15 having frontv and rear endl plates `or anges 1-6 and 1-7. The winding drum or reel l''is-keyed-o'r' otherwise secured for rotation with the shaft'M and thetow cabley 8 is wound thereon and yunreeledy therefrom. f

'angedior vgrooved pulley or brake disc 18 is pinned or keyed onthe\shaft- -14with a V belt 19 surrounding the' brake-disc 18 and retained in the groove at-the bottom' byl the circular guard plate 20.

N guide bushing 21 projectsV radially inward toward the axisl off the'shaft 14-in the plane of the brake drum personnel in the aircraft.

this'n shaft being i journalledl in substantial' alignment with shutter: valve for closingfI and: opening; thel forwardend' i ,ofv thecasingtocprevent: or admit; air; from the air; stream passingthei fuselage intorthe turbine wheel duringight tov control rotation'v of the windinglreel. e

@ther obje'c'tsand advantages of 'the invention will become apparent-1v from the-following;descriptibn' and ac- Thefront: or forward endshell 11 of the casing 9 and the hub member 12' carry bearing means 29 and 30h; whichwissjournalled an air-driven turbine wheel shaft 31,

tliecable reel shaft 14- and extends forwardly, having an airfturbine wheel 32 fixed thereon as shown, a shell at'ifits? forward face.

The reference numerals 33a' indicate the blades which v 33 beingt'xedto-the hub of the turbine or fan wheel 32 VAtraverse a truncated conical ring section 3S with its apex facing forwardly. A cylindrical housing or air intake shell 34 extends forwardly from the front plane and periphery of the turbine wheer 32 and the rearwardly flared ring 35 is secured to the rear end of this housing 34 and surrounds the periphery of the turbine or fan wheel 32 in closely spaced relation. The housing 34 and ring 35 are rigidly supported in spaced relation from the casing 9 and plates 12 and 13 by a plurality of tubular supports or rods 36, these being secured to the casing 9 by fastenings 37. At the forward end of the casing 9 the rods diverge outwardly at 38 and are then bent as at 39 to lie next to the bevel ring 36 and along the outer periphery of the cylindrical housing 34. Brackets or feet may be provided for anchoring the rods or pipes 36 as shown in Figure 4.

A butterfly valve 41 is provided to close or control the entrance of the air stream into the forward `end of the housing 34, this valve 41 being fixed on a transverse shaft 42 which is journalled in diametrically yopposite sides of `the casing and a crank arm 43 is ixed on one end of the shaft 42 for opening and closing the valve. A spring 44 is connected to the crank 43 for biasing the same in one of its maximum positions. A pull cable 45 is connected to a clip 45a on the crank 43 and leads to a suitable setting lever or actuator within the aircraft fuselage, providing the means for rotating the valve 41 to its other extreme position, or other intermediate positions.

When the valve 41 is opened the air from the stream strikes and rotates the turbine wheel 32, and when closed it interrupts the air, allowing the tow line to out reel" under the influence of air drag on the tow target 6, under `control, of course, of the brake device 18-19-22 etc., which can be set to hold the winding reel 1S from rotation after any desired length of tow cable 8 has been unwound from the reel 15.

The winding reel is preferably rotated at a slower rate than that of the turbine wheel 32 and a jack shaft 45, Figure 5 Iand reduction gear train 47, 48, 49 and 50 are provided for this purpose.

The wind-driven tow target device is provided with suitable supporting brackets 51 and 52 (Figure l) Where by the same may be detachably suspended from suitable brackets 53C and 54c depending from the bottom of ,the fuselage of the aircraft 1, for instance, these may be similar to rocket launcher brackets or a bomb rack, so that the device may be ditched in an emergency.

The tow line 8 enters the casing 9 through an elongated opening 53, best seen in Figure l, through a level wind guide means 54, having a cable guide opening 55 therein and side rollers 56 and 57. The guide means 54 is mounted near its bottom on -a reverse winding cam shaft 58 which is suitably journalled at its front and rear ends in bearing members 59 and 60 xed to and projecting from the outer surface of the casing 9, opposite the end plates or discs 12 and 13.

The upper end of the cable guide 54 travels in a slot 61 on an elongated guide plate 62 which is fixed at its ends to the casing 9, above the opening 53 and extends across the top of this opening.

The level wind cable guide means 54 travels back and forth upon continued rotation of the shaft 58 in the same direction, in a well known manner such as by a pivoted guide block on the guide means sliding in a Continuous cam groove 5ba in the shaft S8.

The shaft 5S is driven from the cable reel shaft 14 by a worm-drive reduction gear train. A gear box 63 carries a worm wheel 64 meshing with a worm 65 which is drivingly engaged with the rear end of the shaft 14 at 66, comprising, in effect, a rearward extension on the tow reel shaft 14.

The worm wheel 64 is fixed on a transverse shaft 67, suitably journalled in a transverse housing 68, and is drivably connected to the reverse wind shaft 58 by suitable gearing 69 located in a gear box 70, fastened to rear end plate 13 through the support, for the rear bearing 60 of the reverse wind shaft 58.

Operation Since the device is wind-driven on the inhaul and the drag of the tow target 6 provides the outhaul power on the tow cables there is no particular problem or necessity for auxiliary power for rotating the reel with an electric motor etc., particularly on the inhaul action. When the tow target is fully reeved into its nose receiving wing tip tank support the cable drum 15 is fully wound up and the tension on the tow cable is suicient -to stop the turbine wheel 33 from rotating, without danger of snapping the tow cable d although the shutter 41 may be partly closed or brake applied to slow down excessive inhaul action,

Starting with the tow target 6 fully reeled in, as shown in full lines in Figures 5 and 6, which is, of course, the condition for take-oit and landing, the butterfly valve 41 being also held closely by the spring 44 with the brake band 19 set, and it is desired to rcel out the target, the pilot or operator in the tow plane releases the tow target brake lever (not shown), releasing (or loosening) the brake 19. The slip stream passing the tow target holder 4, and striking the tow target 6, will drag and withdraw it rearwardly from its holder, pulling out the cable 8, causing it to unwind from the cable drum 15. The turbine wheel being out of the slip stream, because of the closed buttery valve 41, will act `as a damper, or governoriiy wheel and through the gearing 42, 4S, 49 and 50, prevent too free or fast out-reeling of the tow line.

After suicient line has been let out and the target 6 is in the trailing position desired, one or more thousand yards behind the tow plane, the brake 8 can be applied, 'also the shutter valve 41 can be partially opened, if desired, to assist in slowing down the outhaul caused by the drag of the air stream on the tow target and its extended tow line.

When it is desired to reel in the target the pilot, or operator, manipulates and sets the butterfly valve control lever (not shown), which can be adjustable to a variety of positions between fully open and fully closed valve position. When the valve position control lever, just mentioned, 'is pulled a cable attached thereto turns the crank 43 against the tension of the spring 44 to adjust the butterfly valve 41, allowing the slip stream passing the aircraft to enter the casing 34 and strike the blades 33 `of the turbine wheel 32, rotating the same to drive, through the reduction speed gearing, the cable drum 15 to wind up the tow target cable 8 and retrieve the tow target. Continued rotation of the reel 15 under the inuence of the air-driven turbine will nally pull the nose of the tow target into the rear end of the receptacle or holder 4, after which the brake 19 can be applied to prevent unwinding action and the aircraft can be landed and the target inspected. The butterfly or plate valve 41 may be adjusted to slow down the entrance of the tow target into the holder, if desired, and closed to prevent air from entering the housing 9 at any time. The operation of the brake and butterfly valve control levers, through the connecting cables 28 and 45 to the brake -and the butterfly valve respectively, control all movements of the cable 8 and the tow target position. Since the winding reel holds a very great length of tow target cable the level winding device 54, driven from the winding reel shaft 14, is provided, this device moving the cable guide back and forth as the reel rotates, provides a uniform and level winding of the cable on the drum in an obvious manner.

If desired, a flexible (Bowden) wire from the rear end of the worm wheel shaft 67 to the pilots instrument lpanel may be provided, together with a suitable dial and indicator operated thereby, calibrated to indicate the length of tow line extended or the distance between the towing aircraft and the tow target in an obvious manner and for an obvious purpose. accomplished by electrical means.

The rods 38 space the cable reel housing 9 from the turbine wheel housing 34 and the space around the stream line nose lll on the reel housing 9 provides free escape of the air that enters the turbine wheel housing after it rotates the turbine wheel 32. The nose spinner or shell 33 retards and defiects the air in front of the turbine wheel outwardly toward the outer portions of the turbine wheel and blades 33a.'

As seen in Figure l and mentioned before, any suitable quick release supporting hangers for the device may be provided, such as the rearwardly notched forward bracket 53c and the quick release rear bracket 54, together with suitable disconnects in the brake and butterfly control cables 28 and 45.

It will be understood that the above description and accompanying drawings comprehend only a general and preferred embodiment of the invention and that various changes in the construction, proportion and arrangement of the parts may be made by those skilled in the art without departing from the nature and scope of the invention, as defined in the appended claims.

l claim:

1. A wind-driven tow target reel, comprising an elongated inclosing casing support, a tow target cable reel journalled within said casing on an axis disposed longitudinally within said casing, said casing having an elongated tow cable receiving opening in one side thereof, opposite said cable reel, tow target cable guide means movable back and forth across said opening for level winding of a tow target cable ony said cable reel between the opposite ends of the cable reel, gear drive means between the cable reel and said guide means for driving said guide means back and forth incident to continued rotation of said cable reel, a cylindrical housing disposed in forwardly spaced substantially aligned relation to the forward end of said casing, an air turbine Wheel having its periphery substantially traversing the rear end inner periphery of said cylindrical housing, drive means between said turbine wheel and said cable reel for effecting rotation of said reel from said turbine wheel, and adjustable closure means in the forward end ofv said housing adapted to open the forward end of the housing to admit air thereinto when the tow target reel device is mounted on the exterior of an aircraft in Hight for rotating said turbine wheel to cause a winding of a tow target cable on said reel, and movable to close said housing to prevent the air stream from entering and rotating the turbine wheel, whereby to permit reverse rotation of said reel and unwinding of the tow target cable therefrom under influence of drag on a tow target attached to the tow cable.

2. Apparatus as claimed in claim 1, including adjustable brake means in said casing for braking and holding said reel stationary to arrest or prevent the unwinding of the tow target cable therefrom.

3. A tow target cable reel device fixed to the exterior of the fuselage of an aircraft adjacent the bottom thereof substantially opposite a tow target receiving support, said tow target cable reel device comprising an elongated cylindrical casing having tapered front and rear ends facing forwardly and rearwardly respectively relative to the flight axis of said aircraft, said casing having an elongated opening in the side thereof facing said tow target receiving support for receiving the tow cable therethrough, a tow target cable reel journalled within said casing on an axis substantially parallel to the said fiight axis, a drive shaft journalled in said casing and extending forwardly beyond the front end of the casing, reduction drive gear means connected between said shaft and said reel for rotating said reel from said drive shaft at a slower relative speed, an air-driven turbine fixed on the forward end of the drive shaft for rotating said shaft .from the slip stream air passing said fuselage, a cylindri- This may also be cal housing surrounding the periphery of said air-driven turbine and extending forwardly thereof to direct air entering the forward end of said housing through said air turbine for actuation thereof, a butterfiy valve for closing the forward end of said housing, spring means between the housing and butterfly valve for moving said butterfly valve toward one of its open or closed positions, cable means connected to said butterfly valve for rotating said valve to its opposite position, spaced longitudinal supporting means fixed to the exterior of the casing and extending forwardly beyond the periphery of said air turbine and connected adjacent their forward ends to said housing for supporting said housing in spaced aligned relation to said casing.

4. Apparatus as claimed in claim 3, including a brake drum connected for rotation with said cable reel, brake means carried by said casing for engaging said drum to control rotation of said reel, and cable means connected to said brake means for brake application thereof.

5. Apparatus as set forth in claim 4, including level wind cable guide means for guiding said tow cable onto said cable reel and movable back and forth across said cable receiving opening in said casing, a worm shaft extension projecting rearwardly from said cable reel shaft, a worm wheel meshing with said worm shaft, a level wind drive shaft drivably connected to said Worm wheel, and reciprocatory drive means connected between the last mentioned cable guide means and level wind drive shaft for reciprocating said tow cable guide means -back and forth across said cable receiving opening in said casing incident to rotation of said cable reel in reeling in and paying out the tow cable.

6. In an aircraft tow target winding reel, a cylindrical winding reel casing having spa-ced end plates, and formed with an elongated rectangular tow cable receiving opening extending longitudinally between said end plates, a cable reel shaft journalled in said end plates for rotation concentrically within the casing, a tow cable reel surrounding said shaft and fixed thereto, tapered closure shells for the front and rear ends of said casing to close the same, a turbine wheel drive shaft journalled in said forward end plate and the tapered front end shell and extending forwardly from said forward end shell for a material distance, reduction drive gearing between said turbine wheel drive shaft and said cable reel shaft for rotating said cable reel at a slower rate than the rate of rotation of said turbine wheel drive shaft, an air-driven fan turbine wheel fixed on the forward end portion of said turbine wheel drive shaft for rotation thereof having a diameter greater than the diameter of said casing, a cylindrical housing disposed in concentric forwardly spaced relation to the periphery of said air-driven fan turbine wheel, and an outwardly and rearwardly extending annular rim surrounding the periphery of the turbine wheel in closely spaced radial relation thereto, supporting rods disposed longitudinally along said casing and housing in spaced relation around the casing and housing and fixed thereto for supporting said housing forwardly from said casing, a butterfly valve journalled in the forward end of said housing for closing the same to prevent air entering said forward end and striking said air-driven fan turbine wheel, a brake drum xed on said cable reel shaft, brake means fixed to said casing and engaging said brake drum to control the rotation of said cable reel, cable means connected to said butterfiy valve and said brake means for selectively actuating said butterfly valve and said brake means to control winding and unwinding action of said cable reel.

References Cited in the file of this patent UNITED STATES PATENTS 2,183,540 Campbell Dec. 19, 1939 2,464,073 Cotton Mar. 8, 1949 FOREIGN PATENTS 695,519 Great Britain Aug. 12, 1953 

